What is the “Registro Único de Arrendamientos” (Spain's register of short-term lets) and who needs it?

Question

José Manuel Alburquerque · Accepted Answer

It was a national register, created by Royal Decree 1312/2024, which assigned a number to each home or room that someone wished to offer on platforms as a short-term let, whether a holiday let or a seasonal let. Without that number, the platform could not publish the advertisement. The “Tribunal Supremo”, Spain's Supreme Court, annulled it in May 2026 because the State does not have the power to create that register, so nobody needs that number today. The “Ventanilla Única Digital de Arrendamientos”, the Digital Single Window for Rentals, to which platforms send data on their activity, remains in place. In Catalonia, holiday lets still need to be entered in the “Registre de Turisme de Catalunya” (the Catalan tourism register) and, in many municipalities, need planning permission. What the Supreme Court annulled The Supreme Court largely found in favour of the tourist apartment associations and the Generalitat Valenciana, the Valencian regional government, which had challenged the royal decree. In its judgment 629/2026 of 21 May, it declared void the articles of the royal decree that regulated the registration procedure and the number. The judgments rest on these grounds: The register served to control an economic activity and obtain information. It was an administrative register, not a civil-law one like the “Registro de la Propiedad”, the Land Registry, so the State could not rely on its power over such registers. Housing and tourism are matters for the autonomous communities, Spain's regions, which already had their own registers. The national one overlapped with them. The State's powers over economic planning and the equality of citizens were not enough to support such comprehensive regulation. Anyone who has already obtained the number does not need to do anything else. Platforms can no longer require it on the basis of the royal decree. What remains in place The Digital Single Window for Rentals, run by the Ministry of Housing. Platforms must send it data on their activity, such as the nights let, the number of guests and their country of residence. It is an obligation of the platforms, not of the owner. Since 8 October 2026, the “Ley de Arrendamientos Urbanos” (LAU), Spain's urban tenancies act, has punished platforms that do not send that data with fines of up to one million euros, which can rise to 2 % of their worldwide annual turnover. It does not affect landlords or tenants. Since that same date, advertisements for residential lettings must include, among other details, the home's number or code if it has one, such as the registration number of holiday lets. The Supreme Court has not said that there cannot be registers of these lettings, but that the State could not create this one. The regional registers remain in force. What the owner needs in Catalonia If you let a flat as a holiday let, entry in the Catalan tourism register, with the number in all advertisements. In the 262 municipalities to which Catalan Decree-Law 3/2023 applies, including Barcelona, planning permission as well. If you let on a seasonal basis, lodging the statutory deposit (the “fianza”) with the “INCASÒL”, the Catalan public body that holds tenancy deposits, together with the document proving the reason for the temporary tenancy. If you let by rooms, lodging the statutory deposit for each contract and registering its details and purpose in the same register.